To answer this question, we can translate this situation algebraically as follows:
[tex]75+25x=200[/tex]Sadie already has $75 saved, and still needs to save what is earned each week at McDonald's ($25 per week). Then, solving for x, we have:
1. Subtract 75 from both sides of the equation:
[tex]75-75+25x=200-75\Rightarrow25x=125[/tex]2. Divide both sides of the equation by 25:
[tex]\frac{25x}{25}=\frac{125}{25}\Rightarrow x=5[/tex]Therefore, Sadie has to work for 5 weeks to earn enough money to buy the sneakers.